A big security lapse in the Babupara VIP colony, where ministers, MLAs, top bureaucrat officers and other government officers including chief minister’s residence are located surfaced, when an armed youth suspected to be underground activist locked down a residence cum office of an engineer on December 14. On December 14 last, an armed youth suspected to be underground activists intruded the high security zone and locked down the residence cum office of the executive engineer of PHED Thoubal division. Police have registered a case against unidentified persons and have started investigation, source said.